Well I found out why the head unit makes the quick static noise on the beginning of some tracks. This is somewhat technical. While ripping the tracks to mp3's, some software inserts a VBR header at the beginning of the track, to let the player know it's a VBR mp3. Well, some not so great players don't know what to do with this info. In the case of our head units, you get a split second static noise. Very annoying. Most good software will allow you to turn off that option, no more noise.
FWIW, I use Exact Audio Copy (EAC) and use the Lame 3.92 codec for compression. No more static!